The present invention relates generally to improved methods and devices for the removal of dental crowns from teeth. Traditional methods for the removal of dental crowns include those such as the following.
Anderson, U.S. Pat. No. 4,179,816 discloses a method for the removal of crowns wherein a hole is made in the occlusal surface of the crown and the margins of that crown are undercut in order that a device with lateral projections may be inserted to lift the remaining portion of the crown off the tooth.
Lococo, U.S. Pat. No. 4,230,454 discloses a method for removal of teeth whereby indentations are drilled in the buccal and lingual sides of a tooth. A tool with the two hemispherical tips for engaging the indentations so drilled is attached to the tooth which is then extracted by application of force on the instrument utilizing a plate placed across adjacent teeth as a fulcrum.
Brantley, U.S. Pat. No. 2,430,271 discloses a device for extraction of teeth comprising pivoting, opposing clamping members for attachment to a tooth to be removed. A lever supported by a base on an adjacent tooth is used to lift the clamping members, vertically removing the tooth.
Lynch, U.S. Pat. No. 4,474,500 discloses a method by which a porcelain crown is removed by means of a noose which is lifted upwardly from the tooth while pressing down against a screw drilled through the crown and resting on the tooth stub below.
Planert, PCT Abstract of WO 87/02573 discloses a device for removing crowns comprising an extraction frame to which two mutually opposed folding jaws are provided to ensure a grip on the crown. The device further comprises a movably supported mass which is guided in a movement track to strike an anvil linked to the extraction frame. The impact of the movable mass against the anvil serves to break the cement bond of the crown with the tooth stub.
Machat, U.S. Pat. No. 2,172,478 discloses a long-handled tooth extracting instrument comprising a metal end which is inserted into a hole drilled in the tooth to be removed. The instrument further comprises a spur and a protective covering which are rested on the top of the tooth adjacent from that to be removed. The adjacent tooth is then used as a fulcrum and the instrument is utilized to apply a large amount of force and thus remove the tooth.
Goldenthal, U.S. Pat. No. 4,197,647 discloses curved, scissors-like dental pliers having a pair of fulcral projections to the rear of the pivot point. The pliers include cushioning pads for gripping dental work such as crowns. The dental work may be removed by gripping with the cushioning pads and using the pliers as a lever forcing the fulcral projections down onto a support member placed across teeth across the mouth from that subjected to the procedure.
Such traditional methods for the removal of crowns tend to be less than completely satisfactory for a number of reasons. Such methods may tend to damage or destroy crowns or may be overly complex in their execution. For those reasons, there exists a need for an improved method for the removal of dental crowns.